NATIONAL ACADEMY OF SCIENCES HENRY PRIMAKOFF 1914—1983 A Biographical Memoir by S . P . ROSEN Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1995 NATIONAL ACADEMIES PRESS WASHINGTON D.C. HENRY PRIMAKOFF February 12, 1914–July 25, 1983 BY S. P. ROSEN ENRY PRIMAKOFF, THE FIRST Donner Professor of Physics Hat the University of Pennsylvania, was a theoretical physicist well known for his contributions to condensed matter physics and to high energy physics. His name is associated with spin waves in ferromagnetism, with the photo-produc- tion method for measuring the short lifetimes of neutral mesons, and with an underwater shock wave. He became a leading authority on weak interaction phenomena in nu- clei, such as double beta decay, muon capture, and neu- trino scattering. He was an outstanding teacher and had a unique influence upon all of his students. EARLY YEARS Henry Primakoff was born in Odessa, Russia, on Febru- ary 12, 1914, and died in Philadelphia on July 25, 1983. In life he had come a long way, from an early childhood in a city beset by war and revolution, through an arduous and often dangerous journey from Russia into Romania and across more than half of Europe, from Bremen to the lower Bronx, and ultimately to the City of Brotherly Love where a long battle with cancer awaited him. In sickness and in health, Henry bore himself with great courage and zest for life and his final years were filled with as much involvement in the 267 268 BIOGRAPHICAL MEMOIRS world around him as at any other period of his life. He died peacefully in the midst of his family. Through his mother, Henry was descended from a large, assimilated Jewish family of merchants who had lived in Odessa for several generations. Through his father, Henry came from a Greek-Orthodox family of wealth and pres- tige. His paternal grandfather married a Jewish woman and was banished from the family estate; years later his father did the same. After the Russian Revolution, one granduncle rose to become a general in the Red Army, but he was executed by Stalin in the famous 1937 purge of the army. Khrushchev subsequently rehabilitated General Primakoff, and a statue in his honor is said to stand in Kiev. Henry’s father was born in Kiev, studied medicine, and graduated as a doctor in 1911. His mother, a strikingly beau- tiful woman, came to Kiev to study pharmacy after graduat- ing from the gymnasium in Odessa, and it was through the medical connection that his parents met. During the First World War his father became an army doctor and was wounded while operating on soldiers behind the front lines. He joined his wife and young son in Odessa at the end of the war, but died a few months later in 1919. At his funeral the Red flag was flown and the Internationale sung. About two years later, Henry’s mother and her parents decided to leave Russia and join an uncle who had settled in New York. This required escaping across the nearest bor- der, the Prut River, into Romania, trudging for long night hours through woods, and hiding by day in remote farm- houses. Eventually they found a haven on the farm of some relatives about five hours by train from Bucharest. Henry was instructed not to talk to his mother when they went into town, because it was too dangerous to speak Russian in that part of Romania at that time. He and his family re- ceived travel documents from the embassy of the Kerensky HENRY PRIMAKOFF 269 government in Bucharest and set out on the long train journey through war-torn Europe to Bremen, and thence on the steamship “der Flieger” to New York, where they finally settled in 1922. Once established in the lower Bronx, Henry made rapid progress in his new language and in school, although he had some startup problems with four-letter words. They were used so frequently by his classmates that he took them to be a normal form of greeting. One day a much bigger kid approached him with a friendly “Hi!,” to which Henry gave a four-letter response. The kid recoiled in astonishment and prepared to slug this insolent, foul-mouthed immigrant; but fortunately for Henry, some other kids realized the prob- lem and saved him from a beating in the nick of time. From that time on he was much more circumspect in his usage of four-letter language. In high school Henry took an active interest in politics and journalism, becoming editor of the school paper one year and president of his class another. He read widely and had an excellent all-around academic record, ending up as second best student in the entire school. He won scholar- ships to Columbia and Harvard and opted for the former despite advice from his granduncle to the contrary. In the fall of 1931 Henry began his freshman year at Columbia. His interests in college were sufficiently broad that he did not become really serious about science until the be- ginning of his junior year. On entering Columbia he was quickly disabused of early ideas for a career in journalism by his experiences on the college paper, and he gave some thought to the study of literature or philosophy. The inter- est in philosophy stood Henry in good stead several years later when he interviewed for the Harvard Society of Fel- lows and was able to hold a lively conversation with the famous philosopher A. N. Whitehead for more than two 270 BIOGRAPHICAL MEMOIRS hours. The fellowship, however, went to John Bardeen, a future Nobel laureate. By the middle of his junior year Henry was concentrating more and more upon physics. He and five or six like-minded students formed an informal club to study special relativity from the short volume by Tolman, which had just been published. The club went on to distinguish itself in the world of physics, its members including Norman Ramsey, Nobel laureate; Herbert Anderson, student of Fermi and co-discoverer of the (3,3) resonance in meson-nucleon scat- tering; Robert Marshak, co-inventor of the universal (V-A) form of weak interactions and founder of the Rochester conferences in high energy physics; and Arthur Kantrowitz, former director of the Avco Everett Research Laboratory. Henry spent his senior year at Columbia taking graduate courses and in one of them, a laboratory course, he met Mildred Cohn, who was to become his wife and a distin- guished chemist known for the application of nuclear mag- netic resonance to biochemistry. During this year the club members became aware of the need for graduate school if they were to become professional physicists; Henry applied to Princeton and was accepted. In those days there was little financial support for gradu- ate studies. One had to be prepared to pay tuition (about $100) and support oneself for at least the first year. With help from his family and money either saved from his un- dergraduate scholarships or earned from various odd jobs Henry managed to stay at Princeton for a year. New York University then offered him a fellowship and he went back to New York to complete his Ph.D. He received his degree in 1938 and married Mildred in May of that year. Despite the bleak economic climate of the times, Henry and Mildred both ended up with jobs in New York, Mildred in the Biochemistry Department of Cornell Medical School HENRY PRIMAKOFF 271 and Henry first at Brooklyn Polytechnic Institute and then at Queens College. After Pearl Harbor he began to work on a navy project concerned with sonar and submarines. Oppenheimer approached him to join the Manhattan Project, but he refused on the grounds that he wanted to work on projects for the present war and not the next one. He did not believe that an atomic bomb could be built in a reason- able time, and was greatly surprised by the news of Hiroshima. When the war ended Henry accepted a joint physics and mathematics appointment at NYU. Richard Courant, founder of the institute that bears his name, wanted to have his mathematicians interact with a physicist and he chose Henry for the job. A year later Arthur Hughes and Eugene Feenberg persuaded Henry to join the physics faculty of Washington University in St. Louis. Mildred eventually arranged to work in Carl Cori’s department at the medical school, and so in 1946 they began a new chapter in their lives in St. Louis, Missouri. PHYSICS RESEARCH Henry wrote his first paper while still a graduate student on “second and higher order processes in the neutrino- electron theory.” In it he and co-author M. H. Johnson calculated the forces between neutrons and protons due to the exchange of virtual neutrino-electron pairs in the new Fermi theory of beta decay. It was a prophetic choice of topic because Henry came to devote a great deal of effort in the postwar era to weak interactions in nuclei. Possibly the best and most significant paper that Henry wrote was also started while he was a graduate student. He and fellow student Ted Holstein were studying the field dependence of the intrinsic magnetization of a ferromag- net at low temperatures when they had the ingenious idea of expressing the spin operators that appear in the Heisen- 272 BIOGRAPHICAL MEMOIRS berg exchange interaction model in terms of boson cre- ation and annihilation operators.